Lacrimal fluid | definition of lacrimal fluid by Medical dictionary Lacrimal fluid | definition of lacrimal fluid by Medical dictionary Related to lacrimal fluid: lachrymation , tears , tares lacrimal fluid a watery physiologic saline, with a plasmalike consistency, but also contains the bacteriocidal enzyme lysozyme; it moistens the conjunctiva and cornea, providing nutrients and dissolved O2 to the cornea. Synonym(s): tears film, precorneal The field covering the anterior surface of the cornea which consists of lacrimal fluid and of the secretion of the meibomian and conjunctival glands. Its total thickness was thought to be about 9 μm but recent investigations have questioned that value and point to a much larger figure. It is composed of three layers: (1) The deepest and densest is the mucin layer (or mucous layer) which derives from the conjunctival goblet cells, as well as some secretion from the lacrimal gland. (2) The watery lacrimal fluid is the middle layer, called the lacrimal (or aqueous layer).

It is secreted by the lacrimal gland and the accessory glands of Krause and Wolfring. It forms the bulk of the film and contains most of the bactericidal lysosyme and other proteins, inorganic salts, sugars, amino acids, urea, etc. (3) The oily layer (or lipid layer) is the most superficial and is derived principally from the meibomian glands in the lids as well as some secretion from the glands of Zeis. It greatly slows the evaporation of the watery layer and may provide a lubrication effect between lid and cornea (Fig. F6). Note: Some authors have suggested that the precorneal film is made up of only two layers; an innermost aqueous and mucin gel layer and an outer lipid layer. Syn. lacrimal layer; preocular tear film; tear film; tear layer. See hyperlacrimation ; mucin ; tear secretion ; Tearscope; break-up time test. Fig.

F6 Diagram of the three layers of the precorneal film attached to the squamous epithelial cells tears The clear watery fluid secreted by the lacrimal gland which, together with the secretions from the meibomian glands, the goblet cells, the gland of Zeis, as well as the accessory lacrimal glands of Krause and Wolfring, helps to maintain the conjunctiva and cornea moist and healthy. Periodic involuntary blinking spreads the tears over the cornea and conjunctiva and causes a pumping action of the lacrimal drainage system, through the lacrimal puncta into the nasolacrimal duct. Approximately 25% of the tears is lost by evaporation, the remaining 75% is pumped into the nasal cavity and over 60% of the tear volume is drained through the lower canaliculus. Tears contain water (98.2%), salts, lipids (e.g. wax esters, sterol esters, hydrocarbons, polar lipids, triglycerides and free fatty acids), proteins (e.g.

lysozyme, lactoferrin, albumin, IgA, IgE, IgG, complement proteins C3, C4, C5 and C9, and beta-lysin), magnesium, potassium, sodium, calcium, chloride, bicarbonate, urea, ammonia, nitrogen, citric acid, ascorbic acid, and mucin. Tears have a pH varying between 7.3 and 7.7 (shifting to a slightly less alkaline value when the eye is closed) and the quantity secreted per hour is between 30 and 120 ml. Syn. lacrimal fluid. See alacrima ; blink ; epiphora ; precorneal film ; hyperlacrimation ; keratoconjunctivitis sicca ; lacrimal apparatus ; lacrimal lake ; lysozyme ; mucin ; fluorescein staining ; break-up time test; non-invasive break-up time test; phenol red cotton thread test; Schirmer's test . artificial tears Any eye drop solution that can replace tears by approximating its consistency in terms of viscosity and tonicity and may contain many of the substances found in tears.

The most common agents found in artificial tears are cellulose derivatives, such as methylcellulose, hydroxymethylcellulose, hydroxypropylcellulose, hypromellose (hydroxypropylmethylcellulose), hydroxyethylcellulose, and polyvinyl alcohol, povidone (polyvinyl pyrrolidine), sodium hyaluronate and sodium chloride, which have low viscosity. Carbomer (polyacrylic acid), carmellose (carbomethylcellulose), liquid paraffin and yellow soft paraffin have medium to high viscosity. Acetylcysteine, a mucolytic agent prepared with hypromellose is used when the tear deficiency is associated with threads and filaments of mucus to soften and make the mucus more fluid, as well as shrinking the mucous membranes (astringent). Syn. ocular lubricant. See alacrima ; recurrent corneal erosion ; ectropion ; dry eye ; hypromellose ; keratoconjunctivitis sicca ; methylcellulose ; Bell's palsy ; wetting solution ; xerophthalmia .

crocodile tears Copious secretion of tears occurring during eating in cases of abnormal regeneration of the seventh cranial nerve after recovery from Bell's palsy. Syn. paradoxic lacrimation. lac·ri·mal flu·id (lak'ri-măl flū'id) The Eyecare Trust - Eyelid and Tear Gland Disorders Eyelid and Tear Gland Disorders Download PDF The eyelids play a key role in protecting the eyes. They help spread moisture (tears) over the surface of the eyes when they close (for example, while blinking); thus, they help prevent the eyes from becoming dry. The eyelids also provide a mechanical barrier against injury, closing reflexively when an object comes too close to the eye. The reflex is triggered by the sight of an approaching object, the touch of an object on the surface of the eye, or the eyelashes being exposed to wind or small particles such as dust or sand. Tears are a salty fluid that continuously bathes the surface of the eye to keep it moist. This fluid also contains antibodies that help protect the eye from infection. Tears are produced by the lacrimal (tear) glands, located near the outer corner of the eye.

The fluid flows over the eye and exits through two small openings in the eyelids (lacrimal ducts); these openings lead to the nasolacrimal duct, a channel that empties into the nose. If the lacrimal glands don't produce enough tears, the eyes can become painfully dry and can be damaged. A rare cause of inadequate tear production is Sjogren's syndrome. The eyes can also become dry when evaporation causes an excessive loss of tears, for example, if the eyelids don't close properly. Nasolacrimal Duct Blockage Blockage of the nasolacrimal duct (dacryostenosis) can result from inadequate development of the nasolacrimal system at birth, a chronic nasal infection, severe or recurring eye infections, or fractures of the nasal or facial bones. Blockage can be partial or complete. Blockage caused by an immature nasolacrimal system usually results in an overflow of tears that runs down the cheek (epiphora) from one eye or, rarely, from both eyes in 3- to 12-week-old infants. This type of blockage usually disappears without treatment by the age of 6 months, as the nasolacrimal system develops.

Sometimes the blockage resolves faster when parents are taught to milk the duct by gently massaging the area above it with a fingertip. Regardless of the cause of the blockage, if inflammation of the conjunctiva (conjunctivitis) develops, antibiotic eyedrops may be needed. If the blockage doesn't clear up, an ear, nose, and throat specialist (otorhinolaryngologist) or an eye specialist (ophthalmologist) may have to open the duct with a small probe, usually inserted through the duct opening at the corner of the eyelid. Children are given general anesthesia for this procedure, but adults need only local anesthesia. If the duct is completely blocked, more extensive surgery may be needed. Lacrimal Sac Infection Usually, infection of the lacrimal sac (dacryocystitis) results from a blockage of the nasolacrimal duct. The infection makes the area around the sac painful, red, and swollen. The eye becomes red and watery and oozes pus. Slight pressure applied to the sac may push pus through the opening at the inner corner of the eye, near the nose. The person also has a fever.

If a mild or recurring infection continues for a long time, most of the symptoms may disappear, with only slight swelling of the area remaining. Sometimes, an infection causes fluid to be retained in the lacrimal sac, and a large fluid-filled sac (mucocele) forms under the skin. Recurring infections may produce a thickened, red area over the sac. An abscess may form and rupture through the skin, creating a passage for drainage. The infection is treated with oral or intravenous antibiotics. Applying frequent warm compresses to the area also helps. If an abscess develops, surgery is performed to open and drain it. For chronic infections, the blocked nasolacrimal duct may be opened with a probe or by surgery. In rare instances, surgical removal of the entire lacrimal sac may be necessary. Eyelid Swelling Anything that irritates the eyes can also irritate the eyelids and cause swelling (lid edema). The most common irritant is an allergy, which can make one or both lids crinkled and swollen. Allergic reactions may be caused by medications instilled into the eyes, such as eyedrops; other drugs or cosmetics; or pollen or other particles in the air.

Insect stings or bites as well as infections from bacteria, viruses, or fungi can also cause the eyelids to swell. Removing the cause of swelling and applying cold compresses may relieve the swelling. If an allergy is the cause, avoiding the allergen can alleviate the swelling; a doctor may also prescribe drug therapy. If a foreign object such as an insect stinger is lodged in the eyelid, it must be removed. Eyelid Inflammation Inflammation of the eyelids (blepharitis) causes redness and thickening; scales and crusts or shallow ulcers often form on the eyelids, as well. Conditions that may occur with eyelid inflammation include staphylococcal infection on the eyelids and in the oil (sebaceous) glands at the edges of the lids, seborrheic dermatitis of the face and scalp, and rosacea. Blepharitis may produce the feeling that something is in the eye. The eyes and lids may itch, burn, and become red. The eyelid may swell and some of the lashes may fall out. The eyes may become red, teary, and sensitive to bright light.

A crust may form and stick tenaciously to the edges of the lid; when the crust is removed, it may leave a bleeding surface. During sleep, dried secretions make the lids sticky. Blepharitis tends to recur and stubbornly resist treatment. It's inconvenient and unattractive but usually not destructive. Occasionally, it can result in a loss of the eyelashes, scarring of the lid margins, and even damage to the cornea. Usually, treatment consists of keeping the eyelids clean, perhaps by washing them with baby shampoo. Occasionally, a doctor may prescribe an antibiotic ointment, such as erythromycin or sulfacetamide, or an oral antibiotic, such as tetracycline. When the person's skin is also affected with seborrheic dermatitis, the face and scalp must be treated as well. Stye A stye (hordeolum) is an infection, usually a staphylococcal infection, of one or more of the glands at the edge of the eyelid or under it. An abscess forms and tends to rupture, releasing a small amount of pus. Styes sometimes form simultaneously with or as a result of blepharitis.

A person may have one or two styes in a lifetime, but some people develop them repeatedly. A stye usually begins with redness, tenderness, and pain at the edge of the eyelid. Then a small, round, tender, swollen area forms. The eye may water, become sensitive to bright light, and feel as though something is in it. Usually, only a small area of the lid is swollen, but sometimes the entire lid swells. Often a tiny, yellowish spot develops at the center of the swollen area. Although antibiotics are used, they don't seem to help much. The best treatment is to apply hot compresses for 10 minutes several times a day. The warmth helps the stye come to a head, rupture, and drain. When a stye forms in one of the deeper glands of the eyelid, a condition called an internal hordeolum, the pain and other symptoms are usually more severe. Pain, redness, and swelling tend to occur in just a very small area, usually at the edge of the eyelid. Because this type of stye rarely ruptures by itself, a doctor may have to open it to drain the pus. Internal styes tend to recur.

Chalazion A chalazion is an enlargement of a long, thin oil gland in the eyelid that results from an obstruction of the gland opening at the edge of the eyelid. At first, a chalazion looks and feels like a stye: swollen eyelid, pain, and irritation. However, after a few days the symptoms disappear, leaving a round, painless swelling in the eyelid that grows slowly for the first week. A red or gray area may develop underneath the eyelid. Most chalazions disappear without treatment after a few months. If hot compresses are applied several times a day, they may disappear sooner. If they remain after 6 weeks, a doctor can drain them or simply inject a corticosteroid. Entropion and Ectropion Entropion is a condition in which the eyelid is turned in against the eyeball. Ectropion is a condition in which the eyelid is turned outward and doesn't come in contact with the eyeball. Normally, the upper and lower eyelids close tightly, protecting the eye from damage and preventing tear evaporation.

If the edge of one eyelid turns in (entropion), the lashes rub against the eye, which can lead to ulceration and scarring of the cornea. If the edge of one eyelid turns outward (ectropion), the two eyelids can't meet properly, and tears aren't spread over the eyeball. These conditions are more common in older people and in those who have had an eyelid injury that caused scar formation. Both conditions can irritate the eyes, causing tearing and redness. Both can be treated by surgery, if necessary. Eyelid Tumors Noncancerous (benign) and cancerous (malignant) growths can form on the eyelids. One of the most common types of benign tumor is xanthelasma, a yellow-white, flat growth that consists of fatty material. Xanthelasmas needn't be removed unless their appearance becomes bothersome. Because xanthelasmas may indicate elevated cholesterol levels (especially in young people), a doctor will check the person's cholesterol level. Squamous cell carcinoma and the more common basal cell carcinoma, both cancerous growths, can develop on the eyelid as well as on many other areas of the skin.

If a growth on the eyelid doesn't disappear after several weeks, a doctor may perform a biopsy (removal of a specimen and examination under a microscope), and the growth is treated, usually with surgery. PTS 1 7 Tears are secreted by a conjunctiva c sclera b - PE - 1400 PTS: 1 7. Tears are secreted by a. conjunctiva c. sclera b. lacrimal glands d. choroid ANS: B Feedback A The conjunctiva is the thin membrane that lines the eyelids and covers part of the eye. This preview has intentionally blurred sections. Sign up to view the full version. View Full Document B C The sclera is the outer layer of the eye. D The choroid is the middle layer of the eye. PTS: 1 8. What separates the outer and middle ear? a. pinna c. organ of Corti b. tympanic membrane ANS: B Feedback A The pinna is the outer ear. B C The organ of Corti is located within the cochlea of the inner ear. PTS: 1 9. Loud noise heard for too long will damage your hearing.

For example, hearing a continuous noise at 100 decibels may damage hearing within how many hours? a. 2 c. 8 b. 4 d. 10 ANS: A Feedback A B At 100 dB, it would take 2 hours to do damage to your hearing. C At 100 dB, it would take 2 hours to do damage to your hearing. D At 100 dB, it would take 2 hours to do damage to your hearing PTS: 1 10. What type of hearing loss results when the ear is blocked by ear wax? a. conductive hearing loss c. mixed hearing loss b. sensorineural damage ANS: A Feedback A B Ear wax causes a conductive hearing loss, not damage to the auditory nerve or inner ear. C Ear wax causes a conductive hearing loss, not damage to the auditory nerve or inner ear. PTS: 1 COMPLETION 1. The wall of the eye is made up of three layers: ____________________, ____________________, and ____________________. ANS: sclera, choroid, retina PTS: 1 2. The innermost, or third coat, of the eye is called the ____________________.

ANS: retina PTS: 1 3. ____________________ is a condition where the lens of the eye gradually becomes cloudy. ANS: Cataract PTS: 1 4. Name the three parts of the ear: ____________________, ____________________, and ____________________. ANS: outer, inner, middle PTS: 1 5. The ______________________________ contain a liquid and delicate hairlike cells that bend when the liquid is set in motion by movement of the head or body. ANS: semicircular canals PTS: 1 6. A sensation of ringing, or buzzing perceived in the ear in the absence of a stimulus is called ____________________. ANS: tinnitus This preview has intentionally blurred sections. Sign up to view the full version. Lacrimal synonyms, lacrimal antonyms - FreeThesaurus.com Lacrimal synonyms, lacrimal antonyms - FreeThesaurus.com of or relating to tears Synonyms relating to or located near the organ that produces tears Synonyms Want to thank TFD for its existence? Tell a friend about us , add a link to this page, or visit the webmaster's page for free fun content . Link to this page: Write what you mean clearly and correctly. References in periodicals archive ?

Two leading characteristics of dry eye syndrome are either insufficient watery tear production from the lacrimal (tear-producing) gland or insufficient oil production from the Meibomian (oil-producing) glands. Assessment of tear amount in subjects under the effect of (inhaled) cocaine Clinical features of the limbal dermoid include "pale yellowish solid mass lesions, which frequently contain hair shafts," as well as "cellular elements from ectodermal and mesodermal origin such as hair fol glands, ectopic lacrimal gland and cartilage," according to the Edward S. Optometrists expand scope of practice: lose battle on laser surgery and "physician" designation Lacrimo-auriculo-dento-digital (LADD) syndrome (OMIM #149730) is a very rare autosomal-dominant congenital multiple anomaly disorder characterized by aplasia (developmental absence of all or part of an organ), atresia (closure or blockage of a body passage), or hypoplasia (underdevelopment or incomplete development) of the lacrimal and salivary systems, cup-shaped ears, hearing loss, and dental anomalies [Milunsky et al.

What is the Lacrimal Gland? (with pictures) What is the Lacrimal Gland? Last Modified Date: 28 December 2016 Copyright Protected: Top 10 unbelievable historical concurrencies The lacrimal gland is a gland that produces one of the components in tears. It is a lobed gland located on the outer side of each eye. These glands produce the aqueous portion of tears, consisting of liquid, salts, proteins and lysozyme. Tears are produced constantly to protect and lubricate the eye, but when additional tears are required to clean substances from the eye or when crying, the lacrimal gland produces the majority of these tears. Major functions of tears include bringing oxygen and other necessary nutrients to the cornea , carrying waste products away from the cornea, preventing the cornea from becoming infected and maintaining the proper levels of saline on the cornea to protect the eye and preserve vision. If the cornea becomes too dry or too wet, eyesight can be affected, causing near- or farsightedness. These changes usually are situational and temporary, but long-term malfunction of the lacrimal gland can lead to chronic conditions such as dry eye.

Other problems with the lacrimal glands include inflammation , infection, or tumors developing in the glands. Swelling in these glands can occur as a side effect of other problems such as Epstein-Barr syndrome or mumps , or it can occur because of bacterial or viral infection. It usually temporary is, but chronic lacrimal inflammation can be a symptom of Sjogren's syndrome, sarcoidosis or other serious conditions. Lacrimal gland infection can lead to problems with the eyes because of reduction of tear production. Any swelling in the area of the eye should be brought to the attention of a doctor. Most infection in these glands can be treated with antibiotics and is a temporary condition, though it might be painful and inconvenient. Another, rarer occurrence is a lacrimal gland tumor. These tumors can be benign or malignant, though a malignant tumor in this area is very rare. Tumors occur most commonly in older people, though they are found in teenage patients as well, at a slightly higher rate than in the general population. In some cases, the tumors are quite small, causing only a mild swelling in the outer eyelid. Other tumors cause severe drooping in the eyelid, sometimes even interfering with vision.

To prevent problems with the lacrimal gland, one should maintain proper eye hygiene and protect the eyes from foreign materials. A doctor or ophthalmologist should be consulted if there are any signs of swelling or discomfort along the outer edge of the eyelid. Using eyedrops can help keep the eye properly lubricated and moist in dry climates, and they help protect the eye and the lacrimal glands. Ad What is the weight of lacrimal gland? anon242127 Post 4 Could you please give me some information about lacrimal gland enlargement and its causes? My CT scan result shows that the lacrimal glands are slightly prominent in both sides (especially the right side), but no bony scalloping or remodeling in lacrimal fossas and no heterogeneity in them. All my thyroid test results are normal, except my TPO. My doctor told me that my lacrimal glands have become bigger. But he has no idea why. I want to know, can crying too much cause this problem? He gave me Prednisolone 50mg, very 12 hours. Thank you very much. pharmchick78 Post 3 @earlyforest -- Sorry to hear about your eyes.

First, to reassure you, it's unlikely that you have lacrimal gland cancer. However, to give you more information (knowledge is power, right), here's a little bit about lacrimal gland cancer. First, there are four main types: benign mixed epithelial tumors, malignant mixed epithelial tumors, lymphomas, and adenoid cystic carcinomas. Those are basically listed in order of seriousness, but don't take it as a harsh standard; all of them can be treated if caught early enough. Benign tumors are obviously the best, but can still need to be removed if they are blocking the gland. The others are more serious, since they can spread to the other parts of the body and are often more difficult to treat. They can also be a sign of a more serious disease, like Hodgkin's lymphoma. Chance-wise, about half of lacrimal tumors are benign and half are malignant, so it is worth getting your eyes checked out if for no other reason than to put your mind at ease. However, chances are that you are more likely to simply have an infection or a cyst, both of which are annoying, yet treatable.

See a doctor; stop messing around with WebMD; you'll just end up worrying yourself more. Hope this helps. EarlyForest Post 2 Hello -- I was wondering if you could give me some information about lacrimal gland tumors. I recently have started getting what seems to be a fairly hard lump in my eye near my lacrimal gland, and I'm really afraid that it is lacrimal gland cancer. Well, I don't know a whole lot about it, but after looking over some lacrimal gland histology pages it seems like that's what it could be. But then it could also be a cyst or a stye or whatever, but I'm just really paranoid that I've got cancer. Could you give me some more information about this subject so I can stop trawling WebMD and freaking myself out? closerfan12 Post 1 I think that lacrimal ducts are one of those things that most people don't think about until it stops working -- I know I used to be like that until I got a very small gland cyst that blocked my lacrimal gland. I still have no idea what caused it, but good Lord, talk about pain!

I just woke up one morning with my eye completely swollen shut, almost like a really bad stye, but with much more pain. I got my husband to drive me to the pharmacy because at that point I still thought that it was just a bad stye, but they told me to go to the doctor, so I went. The doctor diagnosed me immediately with a lacrimal gland cyst, and I ended up having to go into surgery to get it removed the next week. The whole thing was an excruciating, if enlightening experience -- and made me really aware of the design of my eyes, which is a plus, I think. Of course, if I could have gotten the knowledge without the terrible pain that would have been great too... Meibomian Gland Dysfunction and Treatment — AAPOS Intermittent Blurry Vision What is the treatment of MGD? Treatment consists of eyelid/eyelash hygiene to clear off the dead skin, oil and bacterial which build up. The eyelid skin is extremely delicate, so please be gentle. 1) WARM COMPRESSES Heating the eyelid margin will increase oil production and melt the “crusty” oil that has solidified in the glands.

Use a warm (not too hot) wet washcloth to apply heat on the eyelids for four minutes or more. This warms the oil, allowing it to flow more freely, and helps soften lash debris. This should be done twice a day when there are active symptoms, and once a day for maintenance. 2) MASSAGE This can be done while applying the warm compress. Apply light pressure with your finger tips to the lid margin just above the eyelashes. Roll the finger upward on the lower lid while looking up, then roll the finger downward on the upper lid while looking down. Excessive manipulation of the lids can cause additional irritation, so please be careful. 3) LID SCRUBS This helps remove oil, bacteria and debris which block the oil gland openings. Use a Q-tip, your fingers, or a warm washcloth on the tips of your fingers to gently scrub along the lash line on the top and bottom eyelids. Use a mild soap like cetaphil or CeraVe or dilute baby shampoo (a few drops in a small cup of water)- something which will not burn or irritate the eyes. Ask your doctor if you have questions about what to use. Lid scrubs should be done once a day.

4) OMEGA- 3 FATTY ACID: FLAX SEED and FISH OIL In addition to the above, some people benefit from supplementing their diets with omega-3 fats. Omega- 3 fatty acids improve the quality and consistency of the oil produced by the Meibomian glands. Flax seed oil and fish oil are excellent sources of omega- 3 fatty acids. For flax seed oil try 1 teaspoon/day for toddlers or 1 tablespoon/day for older children. Mix with juice, smoothies, or hot cereal. Do not take with blood-thinning medication or blood-sugar lowering medication. There are several companies which make “kid friendly” fish oil and flax seed oil suspensions and gummies (Nordic Naturals and Barleans are two examples). If your child can take pills, there are tablets/capsules which can be taken instead (ex Thera Tears Nutrition). Please talk to your child’s pediatrician if there are any health concerns regarding diet supplementation. updated 04/2016 Lacrimal | definition of lacrimal by Medical dictionary Lacrimal | definition of lacrimal by Medical dictionary [lak´rĭ-mal] pertaining to tears.

lacrimal apparatus a group of organs concerned with the production and drainage of tears; it is a protective device that helps keep the eye moist and free of dust and other irritating particles. The lacrimal gland, which secretes tears, lies over the upper, outer corner of the eye; its excretory ducts branch downward toward the eyeball. A constant stream of tears washes down over the front of the eye and is drained off through two small openings located in the inner corner of the eye. Through these openings the tears pass into the lacrimal canaliculus, then through the lacrimal sac into the nasolacrimal duct and finally into the nasal cavity. The lacrimal apparatus. From Jarvis, 1996. lac·ri·mal /lac·ri·mal/ (lak´rĭ-mal) pertaining to the tears. lacrimal 1. Of or relating to tears. 2. Of, relating to, or constituting the glands that produce tears. lacrimal pertaining to tears. Also spelled lachrymal. lac·ri·mal Relating to the tears, their secretion, the secretory glands, and the drainage apparatus. [L.

lacrima, a tear] lacrimal Pertaining to the tears, to their production and to their disposal. Note that the spelling ‘lachrymal’ has neither logical nor etymological justification. The term comes from Latin lacrima , a tear. lacrimal pertaining to tears. lacrimal apparatus a group of organs concerned with the production and drainage of tears; it is a nutritive and protective device that helps keep the eye moist and free of dust and other irritating particles. Includes lacrimal gland, accessory lacrimal glands, third eyelid glands and the nasolacrimal duct. Nasolacrimal apparatus in the dog.By permission from McCurnin D, Poffenbarger EM, Small Animal Physical Diagnosis and Clinical Procedures, Saunders, 1991 lacrimal canaliculus the lacrimal duct within the eyelid. lacrimal caruncle the rounded, often pigmented swelling at the medial canthus of the eye. lacrimal cyst congenital displacement of lacrimal tissue results in subconjunctival cysts.

lacrimal drainage system the structures concerned with tear collection; includes lacrimal lake, puncta, canaliculi, sac and nasolacrimal duct. lacrimal duct there are two of these minute ducts draining tears from the conjunctiva, via the lacrimal puncta, into the lacrimal sac. Called also lacrimal canaliculus. lacrimal duct irrigator a 20 gauge, blunt-pointed, straight or curved cannula with a needle attachment so that it can be attached directly to a syringe nozzle. lacrimal fossa fossa in the medial wall of the orbital rim which houses the lacrimal sac. lacrimal gland contained in a pad of fat in the dorsolateral part of the orbital cavity and drains into the conjunctival sac via many excretory ducts. The secretion is largely watery tears, but in the pig is mucus. May develop adenitis. lacrimal gland anomalies failure of patency of the duct, supernumerary opening of the duct and ductal ectasia recorded. lacrimal gland atrophy part of the syndrome of keratoconjunctivitis sicca.

imperforate lacrimal puncta see imperforate punctum . lacrimal lake the recess between the lids at the nasal commissure of the eye where the tears collect. lacrimal pump contraction of the orbiculari oculi muscle creates pressure on the lacrimal sac which causes tears to drain from the lacrimal lake. lacrimal punctum there is one on each eyelid close to the medial canthus. Each drains tears from the conjunctival sac into the lacrimal duct in the same eyelid. The tears then pass to the lacrimal sac and into the nasolacrimal duct. See also punctum . lacrimal reflex tear production caused by irritation of the cornea and conjunctiva. lacrimal sac the distended proximal end of the nasolacrimal duct into which the lacrimal ducts empty. lacrimal sinus an excavation of the lacrimal bone which communicates with the maxillary sinus in some species. lacrimal system see lacrimal apparatus (above). Quia - ACCESSORY STRUCTURES AND EYEBALL ANATOMY Java Games: Flashcards, matching, concentration, and word search.

ACCESSORY STRUCTURES AND EYEBALL ANATOMY Tools Name the 5 accessory structures of the eye. Eyelids, eyelashes, eyebrows, lacrimal apparatus, extrinsic eye muscles. A & P name for the eyelids. Palpebrae Thick fold of connective tissue that gives form and support to the eyelids. Tarsal plate Inner lining of the eyelid. Palpebral conjunctiva Outermost covering of the front portion of the eyeball, covers cornea and anterior sclera. Bulbar conjunctiva Glands associated with the hair follicles of the eyelashes are the ___ glands. Sebaceous ciliary glands or glands of Zeis Tears are produced by the ___ glands and pour onto the anterior surface of the eyeball through ___ ___ ducts. Lacrimal glands / excretory lacrimal ducts Tears drain through the superior & inferior lacrimal ___ into the superior and inferior ___ ___. Puncta / lacrimal canals Lacrimal canals empty into the lacrimal ___, which then forms the ____ duct. Sac / nasolacrimal duct Name the extrinsic eye muscles.

Superior rectus, inferior rectus, lateral rectus, medial rectus, superior oblique, inferior oblique. What is the function of the extrinsic eye muscles? Point the eyes in the proper direction, directly toward the object being viewed. The extrinsic eye muscles are which of the 3 types of muscle? Skeletal We call the area where upper & lower lids meet the corner of the eye. What 2 A & P terms are used to name this area? Canthus or commissure The conjunctiva is what type of tissue? Very thin mucous membrane. The area where cornea and sclera meet is called the ___. Limbus The fibrous tunic of the eye consists of what 2 parts? Cornea & sclera What is the A & P name for the white of the eye? Sclera Which 2 eye structures are avascular? Cornea & lens What does avascular mean? No blood vessels The clear window on the anterior surface of the eyeball that allows light rays to reach the pupil is the ___. Cornea The outermost layer of the eyeball is called the ___ tunic? Fibrous The middle layer of the eyeball is the ___ tunic.

Vascular tunic or uvea Name the 3 parts of the vascular tunic, starting at the back of the eyeball. Choroid, ciliary body, iris. Dark brown to black layer that lines the posterior 3/4 of the eyeball. What are the 2 functions of the choroid? Nourishes the retina (by diffusion from its many blood vessels) and absorbs light rays after they once strike the retina. Name the 2 parts of the ciliary body. Clilary muscle and ciliary processes. What is the function of the ciliary processes? Capillaries within them secrete aqueous humor. What is the function of the ciliary muscle? Adjusts the shape of the lens for near & far vision. Name the colored part of the eye. Iris The opening in the center of the iris is the ___. Pupil Size of the pupil is adjusted according to the amount of ___ present. Light Intrinsic eye muscles are part of which 2 eye structures? Iris and ciliary body Intrinsic eye muscles are which of the 3 types of muscle? Smooth Name the 2 functions of the intrinsic eye muscles. Adjust the size of the pupil and change the shape of the lens.

The nervous tunic of the eye is also known as the ___. Retina The anterior edge of the retina is called the ___ ___. Ora serrata Name the 3 layers of neurons in the retina, beginning nearest the choroid. Photoreceptor neurons, bipolar neurons, ganglion neurons. Name the 2 additional type of neurons in the retina, which do not form separate layers but contribute to processing of visual information. Horizontal cells and amacrine cells. Axons of the ___ neurons form the optic nerves. Ganglion Name the 2 types of photoreceptor neurons. Rods & cones The part of the retina that is in the exact center and contains only cones is the___ ___, which is a small depression within the ___ ___. Central fovea / macula lutea The area of no vision in the retina is the ___ ___. Optic disc

Question: What is the common name for the liquid secreted by your lacrimal glands?
Answer: Tears